Integrated circuit packaging technology has seen an increase in the number of integrated circuits mounted on/over a single circuit board or substrate. The new packaging designs are more compact in form factors, such as the physical size and shape of an integrated circuit, and providing a significant increase in overall integrated circuit density. However, integrated circuit density continues to be limited by the “real estate” available for mounting individual integrated circuits on a substrate. Even larger form factor systems, such as personal computers, computer servers, and storage servers, need more integrated circuits in the same or smaller “real estate”.
Particularly acute, the needs for portable personal electronics, such as cell phones, digital cameras, music players, personal digital assistances, and location-based devices, have further driven the need for integrated circuit density. Modem portable electronic devices require a seamless integration of analog and digital subsystems. High-speed digital systems may switch at a high rate, such as more than one gigahertz. At such switching speeds, switching currents radiate energy (noise) that interferes with sensitive analog circuits or even other digital circuits. Interference usually takes the form of signal crosstalk.
Electromagnetic interference (EMI) is a generic term for unwanted interference energies either conducted as currents or radiated as electromagnetic fields. As electronic devices and integrated circuits operate at higher and higher frequencies, EMI extends into the radio frequency spectrum and can cause significant interference with radio and television signals.
One typical scheme has been to provide a conductive enclosure to an electronic device so that EMI field lines will terminate on such enclosure. Unfortunately, conductive enclosures that contain the entire product or parts of the product can be very expensive. In addition, the need to increase integrated circuit density has led to the development of multi-chip packages in which more than one integrated circuit can be packaged.
The trend is to pack more integrated circuits and different types of integrated circuits into a single package require EMI shielding within the package. Typically, metallic or conductive enclosures isolate the various integrated circuits from each other in a package. These conductive enclosures must also be grounded so the EMI radiated energy may be absorbed by the system as opposed to being radiated into the environment or to other integrated circuits. These solutions add manufacture complexity, manufacturing cost, and hamper the size reduction of the multi-chip packages.
In view of the ever-increasing commercial competitive pressures, along with growing consumer expectations and the diminishing opportunities for meaningful product differentiation in the marketplace, it is critical that answers be found for these problems. Additionally, the need to reduce costs, reduce production time, improve efficiencies and performance, and meet competitive pressures, adds an even greater urgency to the critical necessity for finding answers to these problems.
Thus, a need remains for smaller footprints and more robust packages and methods for manufacture. Solutions to these problems have been long sought but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.